Double-tracker musical instrument



Patented Jan. 6,1920.

APPLICATION FILED DEC.l5| 1H5.

M a .h RQWE U U N M T a m M m @m 4 U Y 4710 F. M. MADSEN.

DOUBLE TRACKER MUSICAL INSTRUMENT.

APPLICATION man 020.15. 1915.

Patented Jafi. 6,1920.

4 SHEETS-SHEET 2- INVENTCIR' ,ATTURNEYS F. M. MADSEN.

DOUBLE TRACKER MUSICAL INSTRUMENT.

APPLICATION FILED DEC-15, I915- 1 1,327,342, Patented Jan. 6, 1920.

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ATTEIRNEYE F. M. MADSEN. DOUBLE TRACKER MUSICAL INSTRUMENT.

APPLICATION FILED DEC.15, 1915. 1,327,342, I Patented Jan. 6, 1920.

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FRANCIS M. MADSEN, OF SAN FRANCISCO, CALIFORNIA, ASSIGNOR TO THE RUDOLPH WURLITZER MANUFACTURING COIVIPANY, OF NORTH TONAWANDA, NEW YORK, .A.

CORPORATION OF NEW YORK.

DOUBLE-TRACKER MUSICAL INSTRUMENT.

Specification of Letters Patent.

Patented Jan. 6, 1920.

Application filed December 15, 1915. Serial No. 67,076.

To all whom it may concern:

Be it known that I, FRANCIS M. MnDsnN, a citizen of the United States, residing at San Francisco, in the county of San Francisco and State of California, have invented new and useful Improvements in Double- Tracker Musical Instruments, ofwhich the following is a specification.

This invention relates to the class of automatic musical instruments having a plurality of tracker boards and cooperating music sheets and driving and controlling mechanism by which one of the sheets may be rewound or selections made on it while the other sheet is being taken up or played, such instruments being particularly adapted for moving picture shows where it is desirable to suit the music to the-changing character of the pictures.

The object of my invention is the improvement of such instruments with a view of simplifying their construction, reducing their cost of manufacture and rendering the driving and controlling 'mechanism of the music sheets prompt and reliable in action.

In the accompanying drawings:

Figure 1 is a front elevation of an automatic piano embodying the invention, the sound producing parts which form no part of the invention being omitted for clearness.

Figs. 2 and 3 are diagrammatic sectionalelevations of the instrument, showing different positions of some of the parts. Fig. 4 1s an enlarged vertical longitudinal section ofthe valve-mechanism which controls the air motors. Fig; 5 is an end view of said valve mechanism. Fig. 6 is a transverse vertical section thereof on line 66, Fig. 4:. Fig. 7 is an enlarged side elevation of the keys or controlling levers of the instrument and their connections. Fig. 8 is a transverse sectionof said operating mechanism on line 88, Fig. 7; Fig. 9 is a fragmentary horizontal section on line 99, Fig. 3.

Similar characters of reference indicate corresponding parts throughout the several views.

In the example of the invention shown in the drawings, the instrument has a duplex tracker mechanism, the two tracker boards 1, 2, of which are mounted one above the other in the same stationary box or frame 3 which may be supported on the main action wind-chest 1. Associated with each tracker is the usual music roll or spool 5 and the take-up roll 6. Each take-up roll may be permanently .fjournaled in the frame, while the removable music roll may be engagedfwith the usual horizontal shaft 7 by the customary devices not shown .in the drawings. Arranged counter to the shaft 7 is the customary longitudinally-sliding shaft 8 carrying a pinion 9 which meshes with the gear-wheel 10 of the. take-up roll. The shafts 7 and 8 of each tracker are connected by a sprocket chain 11 running around sprocket wheels 11, 11 mounted on said shafts, the upper wheel 11 being fixed on its shaft while the lower wheel is loose on the pinion shaft 8 and carries a clutch pin or member 12 adapted to be engaged by the corresponding pin of a grooved clutch collar 13 secured to the pinion shaft 8. Each of these pinion shafts is driven by a suitable motor 14, preferably of the pneumatic type, which has the customary crank shaft 15 from which motion is transmitted to said pinion shaft by a sprocket chain. 16 and corresponding wheels.

In the construction shown in the drawings, these clutch collars are shifted by independent levers 17 supported on the tracker-frame and respectively connected by links 18 with upright rock shafts 19, 20, suitably supported in the instrument. These rock shafts are operated by independent controlling levers or keys 21, 22 which are conveniently arranged at the front ofthe key table and extend upwardly and are secured to'the front ends of a pair of parallel rock shafts 23 supported under the key table, as shown in. Figs. 1, 7 and '8. These shafts are pro' vided near their rear ends with unwardlyextending arms 2iwith' which the lower rock arms of the corresponding upright shaft are connected by links 25. The arrangement of the last-described parts is such that when one of the controlling levers 21, 22 is shifted to its extreme right-hand position, the corresponding take-up roll is in a Well-known manner. To predetermine the positions of these controlling levers, an escutcheon plate 26 may be associated with each, these plates bearing suitable indications or abbreviations, such as P1 to indicate the playing position of the lever and Re to indicate its rewind position, as shown in the drawings. In addition to these indications, each plate preferably bears a central abbreviation, such as the letter S, to indicate the select position of the lever, as hereinafter more fully described.

The air motors 14 are controlled by a valve mechanism inclosed in a box or chest 27 which may be conveniently situated below the key table, as shown in Fig. 1. This chest contains two independent valve chambers 28, one for each of the air motors. Each motor has the customary main suction chamber (not shown) which is connected with one of said valve chambers by a tube or conduit 29. Each of these valve chamhers is adapted to be placed under regulated suction or air tension for driving the music sheet forwardly at ordinary speed, or under high air tension for rapidly rewinding the music sheet, or propelling it forwardly rapidly in selecting. For this purpose, each valve chamber is connected by a port 30 with a high tension passage or chamber 31 which in turn is connected with the main suction bellows of the instrument, not shown, by a conduit or passage 32. To the inner end of said port passage is applied a high-tension or rewind valve 33 whose stem is supported in a standard 34 within the valve chamber and in the adjacent wall of the Valve chest27. This valve is normally closed by a suitable spring 35 and opened by the collapse of a pneumatic 36 secured to the adjacent end of said chest. Each valve chamber 28 is also connected with the high tension passage 31 by a regulating or low tension conduit which includes a port 37 extending downwardly from the valve chest, a tempo-valve chamber 38 formed in the lower portion of the valve-chest, a port 39 leading from said chamber into a regulating or equalizing pneumatic or governor 40 and an ascending passage 41 connecting said pneumatic with the high tension passage 31. In the preferred construction shown in the drawings, Figs. 4 and 6, the port 39 opens laterally into the governor-pneumatic and to its lower end is applied a vertically-swinging regulating valve 42 which is controlled by the lower movable board of the governor pneumatic, in such a manner that when the pneumatic is more or less collapsed it partly closes the regulating valve, while when the pneumatic expands, it allows the valve to open to a greater or less extent, thereby automatically regulating the air-tension in the motor and causing it to run uniformly in a common manner. In the construction shown, the regulating valve is pivoted at 43 to a block 44 fixed within the governor pneumatic, while the free end of the valve rests upon the movable board of the lat ter.

Arranged within the lower chamber 38 of the valve chest is a suitable tempo-valve 45 by which the upper end of the connecting port 39 may be constricted more or less, to operate the air motor with greater or less speed, according to the desired tempo of the music. In the drawings is shown a sliding tempo-valve which is mounted on a stem 46 suitably guided in the valve chest 27 and provided external thereto with the customary arm or pointer for actuating it.

To the low-tension port 37 is applied a playing-valve 47 which like the high tension valve 33 is closed by a spring 48 and adapted to be opened by a playing pneumatic 49.

It will be observed that while the valve chambers 28 are duplicated, there is but a single pneumatic governor 40 for both, and a single tempo valve 45 for both.

The low-tension valve 47 of each air motor is preferably so combined with the corresponding clutch-controlling lever 21 or 22 that when said lever is shifted to playing position, said valve is simultaneously opened to acuate the air motor by low or regulated air tension. For this purpose, the opening pneumatic 49 of said valve is con nected by a tube or conduit 50 with one of the valve chambers 51 of an auxiliary action wind-chest 52 which may be located underneath the key table, as shown in Fig. 1.,

This valve chamber communicates with the main suction chamber 53 of said auxiliary chest by a port 54 and with the outer atmosphere by a port 55. These ports are respectively controlled by a double puppet valve 56 of conventional construction which in turn is actuated by an ordinary pouch or primary pneumatic 57. From the chamber of this pouch leads a conduit or duct 58 which terminates at the face of a valve-block 59. The mouth of this duct is controlled by a valve preferably in the form of a spring-pallet 60 fastened at one end to the underside of said block and provided at its opposite free end with a downwardlycurved portion or cam 61 adapted to be tripped by a downwardly-extending finger 62 secured to the adjacent rock shaft 23. By this construction, when the corresponding controlling lever 21 is shifted to playing position, as shown in the left-hand portion of Figs. 2 and 3, said pallet is depressed to its open position, allowing the atmosphere, to enter the conduit 58 and raise the pouch 57 and valve 56, with the result that the valve chamber 51 is connected with the main suction chamber of the auxiliary chest 52 and cut ofi. from, the atmosphere, collapsing the pneumatic 49, opening the lowtension valve 47 and placing the corresponding air-motor under regulated or low air tension, as hereinbefore described.

The controlling pneumatic 36 of each rewind valve 33 is controlled by a similar double-puppet valve 63, but the corresponding ducts 64 of these rewind-pneumatics are controlled independently of the controlling levers 21, 22, by push buttons 65, 66, or equivalent actuating devices, one for each air motor. These buttons act upon valves or pallets 67, applied to the underside of valve blocks 68 in which said conduits terminate.

69 indicates one of the customary striker or motor pneumatics for operating the sound producing parts and which may be carried by the main action wind-chest 4. Each of these striker pneumatics is controlled by the customary double valve 70 and pouch or primary pneumatic 71.

Suitable means are provided for coupling either of the trackers to said main action wind chest and simultaneously uncoupling or cutting off the other. I prefer to employ for this purpose the pneumatic coupler shown in the drawings which is constructed as follows:

72 indicates a coupler board or chest having a central longitudinal partition 73 which divides its chest into two pouch or valve chambers 74, 75, one for each tracker board, each of which chambers is adapted to be exhausted or flushed. Leading to the pneumatic 71 and associated with each striker pneumatic 69 is a channel 7 6 which extends into the partition 73 and has two terminal branches or ports 77, 78, one opening at the upper surface of said partition, and the other at its lower surface, as shown in Figs. 2 and 3. Associated with the two .ports 77, 78 of each channel 7 6 are two indepdendent ports or channels 79, 80 opening at the top of the partition 7 3 adjacent to the port 77, and the other opening at the bottom of said partition adj a-cent to the port- 7 8., The ports 7 9 and 80 are connected by conduit-s 81 and 82 with corresponding note ducts of the twotracker boards, that is, with the two ducts representing the same note. As shown in Figs. 2, 3 and 9, each companionpair of upper ports 77 and7 9 is controlled by a valve, preferably a flexible pouch-valve 83 applied to the upper side of the partition 73, while each companion pair of lower ports 78 and 80 is controlled by a similar pouch valve 84 applied to the lower side of the partition. Vhen, for example, the atmosphere is admitted to the upper. valve-chamber 74 of the coupler, the pouch-valves therein are flattened and pressed against the partition 73, closing the various pairs of upper ports 77 and 79 and cutting oi the upper tracker 1 from the main action wind-chest;

while when said valve chamber is exhausted, said pouch valves are raised, as shown in connection with the upper chamber of Fig. 3, uncovering said upper pairs of ports and allowing the atmosphere to pass from the ports 79 into the ports 77 and actuate those primary pneumatics 71 whose corresponding tracker ducts are uncovered by registering with perforations of the music sheet.

The valve chambers 74, 75 of the coupler are alternately exhausted and flushed through conduits 85, 86 leading to valvechambers 87, 88 of the auxiliary action chest 52, the last-named chambers containing double puppet-valves like the valves 63 previously described. To the pouch-chambers of these two coupler-controllin valves lead air conduits 89, 90, the moutlis of which terminate in the faces of the blocks 59 respectively, adjacent to the air-motor controlling ducts 58 and in line therewith, so as to be controlled by the same pallets 60 which control said motor-ducts. The result is that when one of the controlling levers 21, 22 is moved to playing position, the corresponding air motor is actuated and the corresponding tracker is connected with the main action wind-chest.

It sometimes happens that the operator shifts a controlling lever 21 or 22 and starts the companion motor before attaching the corresponding music sheet to the take-up roll, or he starts the motor while the narrow V- shaped front portion of the sheet is still over the tracker. In either case a number of the note-perforations of the corresponding tracker are left uncovered, producing a dis cord. In order to silence the instrument under these conditions, means are provided for keeping the corresponding coupler-pouches 8-3 or 84 closed until the music sheet has reached the proper position over the tracker, notwithstanding that the corresponding. coupler-controlling valve 87 or 88 has previously been opened. These devices com prise retaining or hold-down auxiliary pneumatics 91, 92 having their movable boards provided with fingers 93 adapted to bear respectively upon the stems of the coupler controlling valves 87, 88. The action of these retaining pneumatics is controlled by double puppet valves 94, 95, arranged in the auxiliary action-chest 52 and identical in construction with the other valves thereof, the pouch chambers of said valves being connected by conduits 96, 97 with independent controlling or retaining ducts 98, 99, respectively arranged in the two trackers, preferably at one end of the rows of noteducts therein, so that the retaining ducts remain covered by the imperforate marginal portions of the music sheets, except when the tapering front portions of the sheets pass over them, or the sheets are out of contact with the trackers. Under the lastnamed conditions, that retaining duct which is temporarily uncovered admits the atmosphere to the pouch chamber of the corresponding auxiliary valve 9% or 95, raising the latter and causing the collapse of the associated auxiliary pneumatic which thereby holds the controlling valve 37 or 38 of the corresponding coupler-chz-imbcr 71 or 75 in its depressed position, even though the coupier-controlling pallet 60 has been opened. Said valve is held depressed until the music sheet to be played has been attached to the take-up roll and its V-shaped portion has passed over the tracker, whereupon the active retaining pneumatic is flushed, and the depressed valve allowed to rise, placing said couplerchamber in communication with the suction-chamber of the auxiliary action chest 52, opening the corresponding pouch-valves 83 or 8 1 and coupling the corresponding tracker to the main action chest. These cut-01f devices act in the same manner in case the wide or main portions of the music sheets should temporarily bulge or rise out of contact with the tracker from any cause.

In order to simplify the control of the instrument and reduce to a minimum the number of acts required of the operator, the tWo controlling levers 21, 22 are preferably coupled together in such a manner that when one is shifted to playing position, the other if in playing position at that time, is simule taneously shifted to stop or select position. F or this purpose, I prefer to employ a pair of links 100 and 101 pivoted at their inner ends to arms 102 and 103, respectively, of the rock shafts 23 and having their inner ends engaged with opposite ends of an intermediate transverse lever 104 by pins 105 carried by said lever and passing through longitudinal slots 106 of the links.

Any suitable means may be employed for holding the controlling levers in position. The preferred device shown in the drawings, Figs. 7 and 9, consists of a spring 107 secured at one end to a support 108 and bear-' ing at its free end upon a cam or enlarge, ment 109 on the hub of the adjacent trip finger 62.

The operation of the instrument is as follows:

When the instrument is silent and at rest, both of the controlling levers 21, 22 are in their central position in line with the indications S in which both pallets 60 are closed, cutting both trackers off from the main action-chest 1 and both air motors from the main suction source by the closure of both sets of high and low tension valves in the valve chest 27 In this central position of the controlling levers, both clutch collars 13 are disengaged from their companion clutch-members.

Assuming now that the main bellows is actuated for exhausting the suction-chambers of the main action wind-chest 1, the auxiliary wind-chest 52 and the passage 31 of the valve chest 27, and that it is desired to play the music sheet of the upper tracker, the operator shifts the left-hand controlling lever 21 to the right, opposite the indication Pl. By this movement the corresponding pinion 9 is shifted into engagement with the gear 10 of the upper take-up roll, and at the same time the corresponding pallet 60 is opened by the finger 62 on the shaft of said controlling lever collapsing the left-haud playing pneumatic 4L9, opening the playing valve 47 and causing the upper motor to op erate under regulated tension. At the same time the valve 87 which controls the upper coupler-chamber 7 4 is raised, connecting said chamber with the main suction chamber of the auxiliary wind chest 52, opening the upper coupler valves 83 and coupling the up-, per tracker to the main action-chest. The upper music-sheet is now taken up and played in the ordinary manner. Although the two controlling levers 21, 22 are linked together, the right-hand lever is unaffected by the movement of the left-hand lever from central to playing position by reason of the longitudinal slots 106 of the links 100, 101 which permit of the necessary limited independent movement of the levers for this purpose. To rewind said upper music sheet, the left-hand controlling lever is shifted backwardly opposite the indication Re and the corresponding rewind button 65 is depressed to open the rewind pallet 67. By

this movement of said lever, the upper clutch collar 13 is connected to the loose wheel 11 of the pinionshaft 8, causing the music roll of the upper sheet to be driven for rewinding the sheet. The depression of the button 65 causes the left-hand rewind pneumatic 36 to be collapsed, opening the corresponding rewind valve 33, connecting the upper air motor directly with the hightension passage 31 and operating it with the desired increased speed. By the movement of the left-hand controlling-lever to rewind position, the corresponding motor and conpler controlling pallet 60 was allowed to close, closing the left-hand playing valve 47 and the puppet-valve 87 which controls the upper chamber of the coupler and cutting off the upper tracker from the main action wind-chest during the rewinding operation of the sheet.

To select a composition on the lower music sheet, for example, the right-hand controlling lever 22 is shifted to central position, as shown in the drawings, and the corresponding rewind button 66 is depressed, whereupon said sheet is rapidly propelled forwardly, owing to its motor being operated by high air-tension. The sheet is arrested at the desired composition by releasing said button, whereupon the right-hand rewind valve 33 is again closed, stopping said motor. For this purpose, the clutch collars 13 are so arranged that they do not engage with the companion clutch members 12 in the central position of the controlling levers, but the pinions 9 are wide enough to remain in mesh with the gears 10 of the take-up rolls both in the central and the playing positions of said levers.

Obviously, the upper music sheet may be played, rewound and rapidly advanced to make selections in the same manner as the lower sheet.

If one of the controlling levers 21, 22 is in playing position, as shown in Figs. 2 and 3, and the other lever is moved to playing position, the first-named lever is automatically returned toits central or stop position to arrest the corresponding music sheet. This action is due to the fact that the pins 105 of the transmission lever 104: are located at the outer ends of the slots 106 of the links when either controlling lever is in playing position and the links therefore cause the levers to move together. At the same time these slots permit either lever tobe moved to rewind position while the other is shifted to or remains in playing position.

As each music sheet has an independent air motor, either can be rewound or selections made on it while the other is playing. If desired, both sheets may be rewound at the same time or selections may be made on both simultaneously, but it is impossible to so manipulate the controlling levers as to play both sheets at the same time. The sheets may be played alternately by simply shifting one or the other controlling lever to playing position, one sheet being promptly stopped at the moment the other is starte as before described. By coupling the controlling levers of the two driving mechanisms, the construction of the instrument is greatly simplified and its cost correspondingly reduced.

The controlling mechanism of the air motors is also materially simplified by utilizing a .single high-tension passage 31, a single higlrtension valve 38 for each motor both for rewinding and selecting purposes, and by employing a tempo-valve and an airovernor common to both motors.

It will be observed that by the single act of shifting either of the controlling levers to playing position, three functions are simultaneously performed, viz: one of the motors is clutched to its respective winding and rewinding mechanism; the valve chamber 28 corresponding to said motor is placed under low tension, and the couplervalves of the corresponding tracker are opened. This not only simplifies the instrument but renders its mampulation more prompt and convenient.

Various modifications coming within the scope of the appended claims, may be made in the instrument, and I do not therefore wish to be limited to the particular embodiment of the invention herein shown and described.

I claim as my invention:

1. In an instrument of the character described, the combination of a plurality of trackers, sheetwinding and rewinding mechanism associated with each tracker, a separate motor for the winding and rewinding mechanism of each tracker, separate controlling member for operatively connecting said motors to the respective winding and rewinding mechanisms, and connecting means for transmitting motion from one of said controlling members to the other.

2. In an instrument of the character described, the combination of a pluralityof trackers, sheet-winding and rewinding mechanism associated with each tracker, a separate motor for the winding and rewinding mechanism of each tracker, separate controlling members for operatively connecting said motors to the respective winding and rewinding mechanisms, and connecting means between said controlling members constructed to permit a limited movement of each member relative to the other.

3. In an instrument of the character described, the combination of a plurality of trackers, sheet-winding and rewinding mechanism associated with each tracker, a

separate motor for the winding and rewinding mechanism of each tracker, separate controlling levers for operatively connecting said motors to the respective winding and rewinding mechanisms, and links operatively connecting said levers.

L. In an instrument of the character described, the combination of a plurality of trackers, sheet-winding and rewinding mechanism associated with each tracker, a separate motor for the winding and rewinding mechanism of each tracker, separate controlling levers for operatively connecting said motors to the respective winding and rewinding mechanisms, a lever arranged between said controlling levers, and links connecting said controlling levers with opposite ends of said intermediate lever.

5. In an instrument of the character described, the combination of a plurality of trackers, sheet-winding and rewindmg mechanism associated with each tracker, a separate motor for the winding and rewinding mechanism of each tracker, separate controll ng levers for operatively connecting said motors to the respective winding and one end to said controlling levers respectively and provided near their opposite ends with longitudinal .slots which engage said pins.

6. In an instrument of the character described, the combination of an action windchest having striker-pneumatic valve-mechanism, a tracker, means for establishing or cutting oii" communication between the tracker and said valve mechanism, and

means controlled by the tracker for render- 10 ing said first-named means inefi'ective except when the music sheet is in proper operative relation to the tracker.

7. In an instrument of the character described, the combination of an action windchest having striker-pneumatic valve -mechanism, a tracker, a pneumatic coupler having a valve-chamber adapted to be alternately exhausted and flushed and passages respectively connected with said valve mechanism and the note ducts of the tracker, couplervalves in said chamber for connecting or disconnecting said passages, a valve controlling the passage of the air to and from said valve chamber, and a retalning pneumatlc controlled by the tracker and acting upon said controlling valve.

8. In an instrument of the character described, the combination of an action windchest having a striker-pneumatic valvemechanism, a-tracker having note ducts and a controlling duct adapted to be normally closed by the music sheet, a pneumatic coupler having a valve-chamber adapted to be alternately exhausted and flushed and passages respectively connected with said valve mechanism and the note ducts of the tracker, coupler-valves in said chamber for connecting or disconnecting said passages, a valve controlling the passage of the air to and from said valve-chamber, and a retaining pneumatic governed by the controlling duct nately exhausted and flushed, said coupler ,having a plurality of sets of passages re spectively connected with the note-ducts of the trackers and also a single set of passages each common to a plurality of like 1noteduct passages and connected with the striker-pneumatic valve-mechanism, coupler valves in each of said chambers connecting -or disconnecting said companion tracker and wind-chest passages, independent valves controlling the passage of the air to and from said chambers, and retaining pneumatics governed by said controlling ducts and acting upon said controlling valves to hold them in position to flush said valve chambers.

10. In an instrument of the character described, the combination of a plurality of trackers, sheet winding and rewinding mechanism associated with each tracker, a separate air motor for the winding and rewinding mechanism of each tracker, means for operatively connecting each motor with the respective mechanism, a valve-chest having separate valve chambers connected with said motors, respectively, a single high-tension air passage common to both of said valve chambers, rewind-valves controlling communication between said valve chambers and said high-tension passage, and means for actuating said valves.

11. In an instrument of the character described, the combination of a plurality of trackers, sheet winding and rewinding mechanism associated with each tracker, a separate air motor for the winding and rewinding mechanism of each tracker, means for operatively connecting each motor with the respective mechanism, a valve-chest having separate valve chambers connected with said motors, respectively, a single high-ten sion air passage common to both of said valve chambers, rewind-valves controlling communication between said valve chambers and said high-tension passage, a single low tension passage common to both of said valve chambers, playing valves controlling communication between said chambers and said low-tension passage, a regulating pneumatic communicating with said low-tension and high-tension passages, a regulating valve for said low-tension passage controlled by said pneumatic, and means for actuating said playing and rewind valves.

12. In an instrument of the character described, the combination of a plurality of trackers, sheet-winding and rewinding mechanism associated with each tracker, a separate air motor for the winding and rewind ing mechanism of each tracker, means for operatively connecting each motor with the respective mechanism, a valve-chest havingseparate valve-chambers connected with said motors, respectively, a single high-tension air Ipassage common to both of said valve chamers, rewind-valves controlling communica tion between said valve chambers and said high-tension passage, a single low-tension passage common to both of said valve chambers, playing valves controlling communication between said chambers and said lowtension passage, a regulating valve for the last-named passage, a regulating pneumatic controlling said regulating valve and communicating with said high and low-tension passages, and a tempo-valve in said low-tension passage.

13. In an instrument of the character described, the combination of an action Windchest, a plurality of trackers, valve mechanism for connecting either of the trackers to the WVIIICl'ChGSt and cutting 01? the other, sheet-Winding and revvinding mechanism associated With each tracker, a separate airmotor for the Winding and reWinding mechanism of each tracker, clutch devices for connecting said motors to the respective Winding and rewinding mechanisms, controlling members for said connecting means, valves for controlling the operation of said motors, and pneumatic mechanism for actuating the last-named valves and said valve mechanism, including air-ducts arranged adj acent to said controlling members and pallets applied to said ducts and controlled by said members.

14:. In an instrument of the character clescribed, the combination of an action Windchest, aplurality of trackers, valve mechanism for connecting either of the trackers to the Wind-chest and cutting ofi the other, sheet windin and rewinding mechanism associated Witli each tracker, a separate air motor for the Winding and rewinding mechanism of each tracker, clutch devices for connecting said motors to the respective Winding and reivinding mechanisms, a rock shaft for each tracker carrying a controlling lever and a trip finger, means for operatively connecting said clutch devices With said rock shaft, valves for controlling the operation of said motors, and pneumatic mechanism for actuating the last-named valves and said valve mechanism, including air ducts having their mouths arranged adjacent to said trip fingers and pallets applied to said mouths and arranged to be opened by said fingers.

15. In an instrument of the character described, the combination of an action Windchest having strikerpneumatic valve-mechanism, a plurality of tracker boards, coupler valve-mechanism for connecting each tracker to said striker-pneumatic valvemechanism, sheet winding and rewinding mechanism for each tracker, a pneumatic motor for each of the last-named mechanisms, means for connecting each motor to the respective Winding and revvinding mechanism, controlling mechanism for each motor, including a low-tension valve for controlling the admission of low or playing tension to the motor, and a single controlling device combined With each tracker, for simultaneously actuating the motor-connecting means, the loW tension valve and the coupler valvemechanism thereof, to take up the music sheet.

16. In an instrument of the character described, the combination of an action Windchest having striker-pneumatic valve-mechanism, a plurality of tracker boards, coupler valve-mechanism for connectingeachtracker to said striker-pneumatic valve-mechanism, sheet Winding and reWinding mechanism for each tracker, a pneumatic motor for each of the last-named mechanisms, means for connecting each motor to the respective Winding and revvinding mechanism, controlling mechanism for each motor including a 10W tension valve for controlling the admission of low or playing tension to the motor, and a hi h tension or rewind valve for controlling 51c admission of high tension to the motor, a single controlling device combined with each tracker for simultaneously actuating the motor-connecting means, the low tension valve and the coupler valve-mechanism thereof to take up the music sheet, and means independent of said controlling devices for controlling the revvind valves of said motors.

17 In an instrument of the character described, the combination of a plurality of trackers, sheet-Winding and rewindingmechanism for each tracker, driving means for said mechanisms, separate controlling members for operatively connecting said Winding and revvinding mechanisms to said driving means, each of said controlling members being movable to positions for playing, re- Winding or stopping the respective notesheets, and means for coupling said controlling memberstogether to automatically move the one to stopping position When the other is moved to playing position.

FRANCIS M. MADSEN. 

